Table 3: Clinical studies of bitter melon (MC).

Study designSubjectDose and durationOutcomeReference

Case study100 moderate noninsulin dependent diabetic (NIDDM) subjectsAqueous homogenized suspension of the vegetable pulpSignificant reduction of both fasting and postprandial serum glucose levels was observed[77]

Case study15 patients of either sex (52–65 years of age) of NIDDM200 mg twice dailywith 7 days treatment plus half doses of metformin or glibenclamide or both in combinationThe extract acts in synergism with oral hypoglycemics and potentiates their hypoglycemia in NIDDM[78]

Randomized, double-blind, placebo-controlled trial40 patients, 18 years old and aboveTwo capsules of M. charantia three times a day after meals, for 3 monthsNo significant effect on mean fasting blood sugar, total cholesterol, and weight or on serum creatinine, ALT, AST, sodium, and potassium[79]

Multicenter, randomized, double-blind, active-control trialThe total of 143 patients were enrolled into the study; 129 patients were randomized to the either metformin (), bitter melon 500 mg/day (), bitter melon 1000 mg/day (), or bitter melon 2000 mg/day ()Bitter melon 500 mg/day, 1000 mg/day, and 2000 mg/day or metformin 1000 mg/day for four weeks2000 mg/day dose showed significant decline in fructosamine at week 4
500 and 1000 mg/day did not significantly decrease fructosamine levels
[80]

Open-label uncontrolled supplementation trial42 eligible (21 men and 21 women) with a mean age of 45.7 ± 11.4 years (23 to 63 years)4.8 gram lyophilized bitter melon powder in capsules daily for three monthsThe metabolic syndrome incidence rate decreased compared to that at baseline
The waist circumference also significantly decreased after the supplementation
[81]

Two-arm, parallel, randomized, double-blinded, placebo-controlled trial19 type 2 diabetic patients taken fruit pulp and 19 type 2 diabetic patients taken as placebo 6 g/day of MC dried-fruit pulp containing 6.26 ± 0.28 mg of charantinSignificant decline of total advanced glycation end-products (AGEs) in serum after 16 weeks of the intervention[82]